Gray cast iron inoculant

Abstract

A ferrosilicon inoculant for gray cast iron containing between 0.1 to 10% strontium, less than 0.35% calcium and either 0.1 to 15% zirconium, 0.1 to 20% titanium or a mixture of both zirconium and titanium with the strontium. The inoculant, method for producing the inoculant, method for inoculating the melt and a gray cast iron inoculated with the inoculant are covered.

What is claimed is: 
     
       1. A ferrosilicon inoculant for cast iron consisting essentially of about 15 to 90% silicon; about 0.1 to 10% strontium; less than about 0.35% calcium; up to about 5% aluminum; not more than about 30% copper; one or more additives selected from the group consisting of about 0.1 to 15% zirconium and about 0.1 to 20% titanium; and a balance of iron, with residual impurities in the ordinary amount. 
     
     
       2. The inoculant of claim 1 wherein the strontium content is about 0.4 to 4%; the zirconium content is about 0.1 to 10%; and the titanium content is about 0.3 to 10%. 
     
     
       3. The inoculant of claim 2 wherein the strontium content is about 0.4 to 1%; the zirconium content is about 0.5 to 2.5%; the titanium content is about 0.3 to 2.5%; and the calcium content is less than about 0.10%. 
     
     
       4. A ferrosilicon inoculant for case iron consisting essentially of about 0.1% to 10% strontium; about 0.1 to 15% zirconium; less than about 0.35% calcium; up to about 5% aluminum; not more than about 30% copper; about 15 to 90% silicon; and a balance of iron, with residual impurities in the ordinary amount. 
     
     
       5. The inoculant of claim 4 wherein the strontium content is about 0.4 to 4%; the zirconium content is about 0.1 to 10%; and the calcium content is less than about 0.15%. 
     
     
       6. The inoculant of claim 5 wherein the strontium content is about 0.4 to 1%; the zirconium content is about 0.5 to 2.5%; and the calcium content is less than about 0.10%. 
     
     
       7. A ferrosilicon inoculant for cast iron consisting essentially of about 0.1 10% strontium; about 0.1 20% titanium; about 15 to 90% silicon; up to about 5% aluminum; not more than about 30% copper; less than about 0.35% calcium; and a balance of iron, with residual impurities in the ordinary amount. 
     
     
       8. The inoculant of claim 7 wherein the strontium content is about 0.4 to 4%; the titanium content is about 0.3 to 10%; and the calcium content is less than about 0.15%. 
     
     
       9. The inoculant of claim 8 wherein the strontium content is about 0.4 to 1%; the titanium content is about 0.3 to 2.5%; and the calcium content is less than about 0.10%. 
     
     
       10. A ferrosilicon inoculant for gray cast iron consisting essentially of about 0.4 to 1% strontium; about 0.5 to 2.5% zirconium; about 40 to 80% silicon; up to about 50% aluminum; not more than about 30% copper; less than about 0.10% calcium; and a balance of iron, with residual impurities in the ordinary amount. 
     
     
       11. A ferrosilicon inoculant for gray cast iron consisting essentially of about 0.4 to 1% strontium; about 0.3 to 2.5% titanium; about 40 to 80% silicon; up to about 5% aluminum; not more than about 30% copper; less than about 0.1% calcium; and a balance of iron, with residual impurities in the ordinary amount.